Rett syndrome


This rare genetic disorder affects the way the brain develops, causing a progressive inability to use muscles for eye and body movements and speech.


Rett syndrome is a rare genetic neurological and developmental disorder that affects the way the brain develops, causing a progressive loss of motor skills and speech. This disorder primarily affects girls.

Most babies with Rett syndrome seem to develop normally for the first 6 to 18 months of age, and then lose skills they previously had — such as the ability to crawl, walk, communicate or use their hands.

Over time, children with Rett syndrome have increasing problems with the use of muscles that control movement, coordination and communication. Rett syndrome can also cause seizures and intellectual disability. Abnormal hand movements, such as repetitive rubbing or clapping, replace purposeful hand use.

Although there's no cure for Rett syndrome, potential treatments are being studied. Current treatment focuses on improving movement and communication, treating seizures, and providing care and support for children and adults with Rett syndrome and their families.


Babies with Rett syndrome typically are born after a normal pregnancy and delivery. Most infants with Rett syndrome seem to grow and behave normally for the first six months. After that, signs and symptoms start to appear.

The most pronounced changes generally occur at 12 to 18 months of age, over a period of weeks or months. Symptoms and their severity can vary greatly from child to child.

Rett syndrome signs and symptoms include:

  • Slowed growth. Brain growth slows after birth. Smaller than normal head size (microcephaly) is usually the first sign that a child has Rett syndrome. As children get older, delayed growth in other parts of the body becomes evident.
  • Loss of normal movement and coordination. The first signs often include reduced hand control and a decreasing ability to crawl or walk normally. At first, this loss of abilities occurs rapidly and then it continues more gradually. Eventually muscles become weak or may become rigid or spastic with abnormal movement and positioning.
  • Loss of communication abilities. Children with Rett syndrome typically begin to lose the ability to speak, to make eye contact and to communicate in other ways. They may become disinterested in other people, toys and their surroundings. Some children have rapid changes, such as a sudden loss of speech. Over time, children may gradually regain eye contact and develop nonverbal communication skills.
  • Abnormal hand movements. Children with Rett syndrome typically develop repetitive, purposeless hand movements that may differ for each person. Hand movements may include hand-wringing, squeezing, clapping, tapping or rubbing.
  • Unusual eye movements. Children with Rett syndrome tend to have unusual eye movements, such as intense staring, blinking, crossed eyes or closing one eye at a time.
  • Breathing problems. These include breath-holding, abnormally rapid breathing (hyperventilation), forceful exhalation of air or saliva, and swallowing air. These problems tend to occur during waking hours, but breathing disturbances such as shallow breathing or periodic breathing can occur during sleep.
  • Irritability and crying. Children with Rett syndrome may become increasingly agitated and irritable as they get older. Periods of crying or screaming may begin suddenly, for no apparent reason, and last for hours. Some children may experience fears and anxiety.
  • Other abnormal behaviors. These may include, for example, sudden, odd facial expressions and long bouts of laughter, hand licking, and grasping of hair or clothing.
  • Cognitive disabilities. Loss of skills can be accompanied by a loss of intellectual functioning.
  • Seizures. Most people who have Rett syndrome experience seizures at some time during their lives. Multiple seizure types may occur and are accompanied by an abnormal electroencephalogram (EEG).
  • Abnormal curvature of the spine (scoliosis). Scoliosis is common with Rett syndrome. It typically begins between 8 and 11 years of age and increases with age. Surgery may be required if the curvature is severe.
  • Irregular heartbeat. This is a life-threatening problem for many children and adults with Rett syndrome and can result in sudden death.
  • Sleep disturbances. Abnormal sleep patterns can include irregular sleep times, falling asleep during the day and being awake at night, or waking in the night with crying or screaming.
  • Other symptoms. A variety of other symptoms can occur, such as thin, fragile bones prone to factures; small hands and feet that are usually cold; problems with chewing and swallowing; problems with bowel function; and teeth grinding.

Stages of Rett syndrome

Rett syndrome is commonly divided into four stages:

  • Stage I: early onset. Signs and symptoms are subtle and easily overlooked during the first stage, which starts between 6 and 18 months of age and can last for a few months or a year. Babies in this stage may show less eye contact and start to lose interest in toys. They may also have delays in sitting or crawling.
  • Stage II: rapid deterioration. Starting between 1 and 4 years of age, children lose the ability to perform skills they previously had. This loss can be rapid or more gradual, occurring over weeks or months. Symptoms of Rett syndrome occur, such as slowed head growth, abnormal hand movements, hyperventilating, screaming or crying for no apparent reason, problems with movement and coordination, and a loss of social interaction and communication.
  • Stage III: plateau. The third stage usually begins between the ages of 2 and 10 years and can last for many years. Although problems with movement continue, behavior may have limited improvement, with less crying and irritability, and some improvement in hand use and communication. Seizures may begin in this stage and generally don't occur before the age of 2.
  • Stage IV: late motor deterioration. This stage usually begins after the age of 10 and can last for years or decades. It's marked by reduced mobility, muscle weakness, joint contractures and scoliosis. Understanding, communication and hand skills generally remain stable or improve slightly, and seizures may occur less often.

When to see a doctor

Signs and symptoms of Rett syndrome can be subtle in the early stages. See your child's doctor right away if you begin to notice physical problems or changes in behavior after apparently normal development, such as:

  • Slowed growth of your child's head or other parts of the body
  • Decreased coordination or mobility
  • Repetitive hand movements
  • Decreasing eye contact or loss of interest in normal play
  • Delayed speech development or loss of previously acquired speech abilities
  • Problem behavior or marked mood swings
  • Any clear loss of previously gained milestones in gross motor or fine motor skills

Rett syndrome is a rare genetic disorder. Classic Rett syndrome, as well as several variants with milder or more-severe symptoms, can occur based on the specific genetic mutation.

The genetic mutation that causes the disease occurs randomly, usually in the MECP2 gene. Only in a few cases is this genetic disorder inherited. The mutation appears to result in problems with the protein production critical for brain development. However, the exact cause is not fully understood and is still being studied.

Rett syndrome in boys

Because males have a different chromosome combination from females, boys who have the genetic mutation that causes Rett syndrome are affected in devastating ways. Most of them die before birth or in early infancy.

A very small number of boys have a different mutation that results in a less destructive form of Rett syndrome. Similar to girls with Rett syndrome, these boys will likely live to adulthood, but they're still at risk of a number of intellectual and developmental problems.


Rett syndrome is rare. The genetic mutations known to cause the disease are random, and no risk factors have been identified. In a few cases, inherited factors — for instance, having close family members with Rett syndrome — may play a role.


Complications of Rett syndrome include:

  • Sleep problems that cause significant sleep disruption to the person with Rett syndrome and family members
  • Difficulty eating, leading to poor nutrition and delayed growth
  • Bowel and bladder problems, such as constipation, gastroesophageal reflux disease (GERD), bowel or urinary incontinence, and gallbladder disease
  • Pain that may accompany problems such as gastrointestinal issues or bone fractures
  • Muscle, bone and joint problems
  • Anxiety and problem behavior that may hinder social functioning
  • Needing lifelong care and assistance with activities of daily living
  • Shortened life span — although most people with Rett syndrome live into adulthood, they may not live as long as the average person because of heart problems and other health complications

There's no known way to prevent Rett syndrome. In most cases, the genetic mutation that causes the disorder occurs spontaneously. Even so, if you have a child or other family member with Rett syndrome, you may want to ask the doctor about genetic testing.


Diagnosing Rett syndrome involves careful observation of your child's growth and development and answering questions about medical and family history. The diagnosis is usually considered when slowing of head growth is noticed or loss of skills or developmental milestones occur.

For a diagnosis of Rett syndrome, other conditions with similar symptoms must be ruled out.

Evaluating other causes for the symptoms

Because Rett syndrome is rare, your child may have certain tests to identify if other conditions are causing some of the same symptoms as Rett syndrome. Some of these conditions include:

  • Other genetic disorders
  • Autism
  • Cerebral palsy
  • Hearing or vision problems
  • Metabolic disorders, such as phenylketonuria (PKU)
  • Disorders that cause the brain or body to break down (degenerative disorders)
  • Brain disorders caused by trauma or infection
  • Brain damage before birth (prenatal)

What tests your child needs depends on specific signs and symptoms. Tests may include:

  • Blood tests
  • Urine tests
  • Imaging tests such as magnetic resonance imaging (MRI) or computerized tomography (CT) scans
  • Hearing tests
  • Eye and vision exams
  • Brain activity tests (electroencephalograms, also called EEGs)

Criteria for diagnosis

A diagnosis of classic Rett syndrome includes these core symptoms:

  • Partial or complete loss of purposeful hand skills
  • Partial or complete loss of spoken language
  • Walking abnormalities, such as problems walking or not being able to walk
  • Repetitive purposeless hand movements, such as hand-wringing, squeezing, clapping or tapping, putting hands in the mouth, or washing and rubbing movements

Additional typical symptoms can support the diagnosis.

Diagnostic criteria for atypical or variant Rett syndromes may vary slightly, but the symptoms are the same, with varying degrees of severity.

Genetic testing

If your child's doctor suspects Rett syndrome after evaluation, he or she may recommend a genetic test (DNA analysis) to confirm the diagnosis. The test requires drawing a small amount of blood from a vein in the arm. The blood is then sent to a lab, where technicians examine your child's DNA for abnormalities and clues as to the cause and severity of the disorder. Testing for mutation of the MEPC2 gene confirms the diagnosis.


Although there is no cure for Rett syndrome, treatments are directed toward symptoms and providing support, which may improve the potential for movement, communication and social participation. The need for treatment and support doesn't end as children become older — it's usually necessary throughout life. Treating Rett syndrome requires a team approach.

Treatments that can help children and adults with Rett syndrome include:

  • Regular medical care. Management of symptoms and health problems may require a multispecialty team. Regular monitoring of physical changes such as scoliosis and GI and heart problems is needed.
  • Medications. Though medications can't cure Rett syndrome, they may help control some signs and symptoms associated with the disorder, such as seizures, muscle stiffness, or problems with breathing, sleep, the gastrointestinal tract or the heart.
  • Physical therapy. Physical therapy and the use of braces or casts can help children who have scoliosis or require hand or joint support. In some cases, physical therapy can also help maintain movement, create a proper sitting position, and improve walking skills, balance and flexibility. Assistive devices may be helpful.
  • Occupational therapy. Occupational therapy may improve purposeful use of the hands for activities such as dressing and feeding. If repetitive arm and hand movements are a problem, splints that restrict elbow or wrist motion may be helpful.
  • Speech-language therapy. Speech-language therapy can help improve a child's life by teaching nonverbal ways of communicating and helping with social interaction.
  • Nutritional support. Proper nutrition is extremely important for normal growth and for improved mental, physical and social abilities. A high-calorie, well-balanced diet may be recommended. Feeding strategies to prevent choking or vomiting are important. Some children and adults may need to be fed through a tube placed directly into the stomach (gastrostomy).
  • Behavioral intervention. Practicing and developing good sleep habits may be helpful for sleep disturbances.
  • Support services. Academic, social and job-training services may help with integration into school, work and social activities. Special adaptations may make participation possible.

A few examples of complementary therapies that have been tried in children with Rett syndrome include:

  • Music therapy
  • Massage therapy
  • Hydrotherapy, which involves swimming or moving in water
  • Animal-assisted therapy, such as therapeutic horseback riding

Although there's not much evidence that these approaches are effective, they may offer opportunities for increased movement and social and recreational enrichment.

If you think alternative or complementary therapies might help your child, talk to your doctor or therapist about the possible benefits and risks, and how the approach might fit into the medical treatment plan.


Children and adults with Rett syndrome need help with most daily tasks, such as eating, walking and using the bathroom. This constant care and disturbed sleep can be exhausting and stressful for families, and can impact the health and well-being of family members.

To better cope with the challenge:

  • Find ways to relieve stress. It's natural to feel overwhelmed at times. Talk about your problems with a trusted friend or family member to help relieve your stress. Take some time for yourself doing something you like to recharge your battery.
  • Arrange for outside help. If you care for your child at home, seek the help of outside caregivers who can give you a break from time to time. Or you may consider residential care at some point, especially when your child becomes an adult.
  • Connect with others. Getting to know other families facing problems similar to yours can help you feel less alone. Look for online support and information from organizations such as RettSyndrome.org.

Your child's doctor will look for developmental problems at regular checkups. If your child shows any symptoms of Rett syndrome, she or he will likely be referred to a pediatric neurologist or developmental pediatrician for testing and diagnosis.

Here's some information to help you get ready for your child's appointment. If possible, bring a family member or friend with you. A trusted companion can help you remember information and provide emotional support.

What you can do

Before your appointment, make a list of:

  • Any unusual behavior or other signs. The doctor will examine your child carefully and watch for slowed growth and development, but your daily observations are very important.
  • Any medications that your child takes. Include any vitamins, supplements, herbs and over-the-counter medicines, and their dosages.
  • Questions to ask your child's doctor. Don't be afraid to ask questions when you don't understand something. If you run out of time, ask to speak with a nurse or leave a message for the doctor.

Questions to ask the doctor might include:

  • Why do you think my child does (or doesn't) have Rett syndrome?
  • Is there a way to confirm the diagnosis?
  • What are other possible causes of my child's symptoms?
  • If my child does have Rett syndrome, is there a way to tell how severe it is?
  • What changes can I expect to see in my child over time?
  • Can I take care of my child at home, or will I need to look for outside care or additional in-home support?
  • What kind of special therapies do children with Rett syndrome need?
  • How much and what kinds of regular medical care will my child need?
  • What kind of support is available to families of children with Rett syndrome?
  • How can I learn more about this disorder?
  • What are my chances of having other children with Rett syndrome?

What to expect from your doctor

Your doctor may ask you questions such as:

  • When did you first notice your child's unusual behavior or other signs that something may be wrong?
  • What could your child do before that she or he can no longer do?
  • How severe are your child's signs and symptoms? Are they getting progressively worse?
  • What, if anything, seems to improve your child's symptoms?
  • What, if anything, appears to worsen your child's symptoms?

Your doctor will ask additional questions based on your responses and your child's symptoms and needs. Preparing and anticipating questions will help you make the most of your appointment time.



Last Updated:

May 5th, 2021

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